覆膜砂及其组合支撑剂导流能力实验研究

Experimental Study on the Flow Conductivity of Coated Sand and Its Combined Proppant

覆膜砂通常被用于控制压裂后的支撑剂回流和出砂,同时,其不同组合下的导流能力也不同。为了更好地指导覆膜砂的现场应用,利用DL-2000型导流仪开展了覆膜砂及其组合支撑剂的导流能力实验。实验结果表明:在测试的闭合压力范围内,覆膜陶粒的导流能力随闭合压力的加大而递减,递减幅度较小;覆膜陶粒的导流能力小于普通陶粒的导流能力,组合支撑剂导流能力居中,与组合比例有关;在相同的闭合压力下,组合支撑剂中覆膜陶粒含量越高,其导流能力越低,且随着闭合压力增大,覆膜陶粒含量高的组合支撑剂导流能力相对递减速度变慢。

Coated sand is one of the techniques to control the flowback and sand production after fracturing, but the use of coated proppant will have different effects on the flow conductivity. In order to better guide the field application of coated sand, this paper tests the flow conductivity of coated sand and its combined proppant by using the test instrument DL-2000. In the closing pressure range of the test, the results show that the conductivity of coated ceramsite decreases with the increase of the closing pressure and the decreasing extent is small. The flow conductivity of the coated ceramsite is smaller than that of the ceramsite. The flow conductivity of combined proppant is between the original proppant conductivity, and the specific value is related to the composition ratio. Under the same closing pressure, the proportion of coated ceramsite in the combined proppant is higher, the flow conductivity is lower. As the closing pressure increases, the flow conductivity of the high-content coated ceramsite decreases slower than that of the low-content coated proppant.